. There's Chris Mcdaniel. Forcing a run-off. It's a boost for the tea party after some setbacks this season that have established republicans feeling good about taking back the senate. The roundtable weighs in after this. Reporter: The tea party announced that it's back with a bang. Oni Ernst, the Harley Davidson mom of three, blew past her rival to capture a republican senate nomination. She's vowing to make Washington squeal. I grew up cast rating hogs on an Iowa farm. When I get to Washington, I'll know how to cut pork. Reporter: The same night Ernst won in Iowa a stunner in Mississippi. Newcomer Chris Mcdaniel forced a primary run-off with a senator since 1978. National tea party groups are backing Mcdaniel, a former radio talk show host. Now comes a three-week sprint of a run-off. Mcdaniel supporters were accused of secretly taping Cochran's bedridden wife. And this attempt to define a Spanish term. Reporter: Mcdaniel's comments have some republicans worried about a rerun of recent tea party tumbles. Could this be a repeat of 2010 or 2012, a candidate ended up doing things that are disqualifying. I think the Todd Aiken things were one time. Reporter: For republicans, though, it guarantees at least a few more weeks of not so friendly fire. For "This week," Rick Kline, ABC news, Washington. We're now back with the roundtable. Let me bring in congressman Cole, you spear headed republican campaigns in the past. Mcdaniel the only real tea party star who's looking to have a chance to win one of these primaries, making a lot of your colleagues excited about the prospects of taking back the senate. I think we'll take back the senate. You look at seven deep red states, we're probably going to win six, or all seven. Iowa, I think we'll win. Colorado, long shots in Virginia. Maybe not quite so long in Michigan and New Hampshire. So, you know, the board looks pretty good. The fights we have had have been spirited. Predicting a kind of wave of the incumbent wave of the white house? It becomes what the current administration is doing and what the president's job approval. The president's job approval is in the low 40s. Which means republicans will pick up seats in the course of this. I think what's interesting about this race in Mississippi, the tea party candidate that have won, it's wasn't about the quote, unquote, the tea party. The constituents became immersed in the status quo. I think Mcdaniel wins this race and he wins in November. Mississippi is red. All of top lines are definitely about the republicans. They got the candidates they want. But I also think there's an interesting conversation happening on the democratic side, where Progressive candidates winning in Iowa and California and New Jersey. Potentially changing the composition of their caucus. I believe we'll narrowly retain the senate, narrowly, but if we lose the senate, I think the president needs to concentrate on global climate change, on executive orders. I think it would be unfortunately, the death nail of immigration reform. What I would do if I were the president in that case, put a moratorium on deportation. I think the senate very narrowly. The president seems to be gearing up for something like that, migrant children, up to 1,000 being brought to centers in Arizona. It's a policy failure much more broadly. I don't think conditions in central America are different than two, three years ago. We made a decision, if you're an unaccompanied minor, you show up in the United States, we're not only going to take you in, we're probably going to keep you, I think that's encouraging news. Not a policy thought. People want to help people in crises, it's the appropriate thing to do. On the other hand, you can't have an open invitation for everybody who comes to the border. I think there's legislation that can easily go before congress, we know what comprehensive immigration policy looks like. We have the same conversation every two years. It's time for congress to act on this. It's no longer a partisan issue. It is a humanitarian crisis. On top of that, it's an economic crisis. We need to be honest. We're out of time. I apologize. We'll be back after this Hey there can I help you? (Whispering) Sorry. (Whispering) Hi, uh we need a new family plan. (Whispering) How about 10 gigs of data to share and unlimited talk and text. (Whispering) Oh ten gigs sounds pretty good. (Whispering) Yeah really good (whispering) Yeah and for a family of 4 it's a $160 a month. What! Get outta here! (Whispering) I'm sorry are we still doing the whisper thing? Or? (Whispering) O! Sorry! Yes yes!

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